Image pickup apparatus and synchronization signal generating apparatus

ABSTRACT

An image signal generation portion  11  generates an image signal of a variable frame-rate picked-up image. A signal generation control portion  24  drives the image signal generation portion  11  and generates image pick-up setting information IF to generate an image signal that is frame-synchronized with a generated image signal DVd. The generated image signal DVd is output in condition where the image pick-up setting information IF is inserted in it. When supplied with image pick-up setting information IFex, the signal generation control portion  24  controls the driving operations of the image signal generation portion  11  based on the image pick-up setting information IFex, to frame-synchronize the generated image signal with an image signal of a reference variable frame-rate picked-up image of a source that has supplied the image pick-up setting information IFex. If a plurality of image pick-up devices capable of varying a frame rate is used, the image signals can be frame-synchronized with each other.

TECHNICAL FIELD

The present invention relates to an image pick-up device and asynchronization-signal-generating device. More specifically, it relatesto supplying an image pick-up device with image pick-up settinginformation from any other image pick-up device or asynchronization-signal-generating device, to drive image signalgeneration means which generates an image signal of a picked-up imagewith variable frame rate based on this image pick-up settinginformation, thereby causing the image signal generation means togenerate a frame-synchronized image signal even if a frame rate of thepicked-up image with variable frame rate is varied.

BACKGROUND ART

In conventional filmmaking etc., to obtain special video effects, sceneshave been shot in condition where a shooting speed of a film camera,that is, the number of frames per second has been varied. For example,if a scene is shot at a higher speed than an ordinary one and reproducedat the ordinary speed, reproduced images are slowly seen. Therefore,fast motion of, for example, a water droplet falling into water can beobserved easily and in detail. If a scene is shot at a lower speed thanthe ordinary one and reproduced at the ordinary speed, on the otherhand, reproduced images can be fast seen. It is thus possible to enhancea sense of speed in a fight scene, a car chase scene, etc., therebypresenting images with an enhanced sense of reality.

Further, in TV program making etc., while an attempt has been made todigitize processing of shooting, editing, delivery, etc. of a program,an attempt has also been made to digitize processing in filmmaking etc.as fueled by an increase in image quality and a decrease in costs causedby progress in digital technologies.

It is noted that if images are to be picked up using an image pick-updevice (video camera) due to digitization of TV program, filmmaking,etc., an image pick-up device described in Jpn. Pat. Appln. KOKAIPublication No. 2000-125210 and supposed to be capable of frame ratevarying is used so that special video effects such as fast reproductionand slow reproduction can be obtained easily. By using this imagepick-up device to pick up images at a lower speed than a predeterminedframe rate and reproduce them at the predetermined frame rate, fastmotion of the reproduced images can be obtained easily. By picking upthe images at a higher frame rate and reproducing them at thepredetermined frame rate, on the other hand, slow motion of thereproduced images can be obtained easily.

In a case where a plurality of image pick-up devices each capable ofvarying a frame rate thereof is used to pick up images of a target indifferent directions, by synchronizing the frames of image signalsobtained by these image pick-up devices with each other, it is possibleto obtain a fast motion reproduction image or a slow motion reproductionimage that has the same speed and has been picked up in the plurality ofdirections. For example, if the target is shot at a higher frame rateand reproduced at a predetermined frame rate, it is possible to obtain aslow motion reproduction image picked up in different directions inwhich the target moves at the same speed. Therefore, by synchronizingthe frames of the image signals obtained by the image pick-up deviceswith each other, it is possible to facilitate subsequent editingprocessing. However, if the frame rates of the image pick-up devices arevaried during image pick-up, it is almost impossible to synchronize theframes of the image pick-up devices through user operations.

DISCLOSURE OF THE INVENTION

An image pick-up device according to the invention comprises imagesignal generation means for generating an image signal of a variableframe-rate picked-up image, drive-and-control means for driving andcontrolling the image signal generation means, setting informationgeneration means for generating image pick-up setting information togenerate an image signal which is frame-synchronized with the imagesignal generated by the image signal generation means, and output meansfor outputting the image signal generated by the image signal generationmeans and the image pick-up setting information.

Another image pick-up device related to the present invention comprisesimage signal generation means for generating an image signal of avariable frame-rate picked-up image, and drive-and-control means forreceiving image pick-up setting information to generate an image signalthat is frame-synchronized with the image signal of a reference variableframe-rate picked-up image, and controlling a driving operation of theimage signal generation means based on this image pick-up settinginformation, thereby frame-synchronizing the image signal generated bythe image signal generation means with the image signal of the referencevariable frame-rate picked-up image.

Further, a synchronization-signal-generating device according to theinvention supplies a synchronization signal to an image pick-up devicehaving image signal generation means for generating an image signal of avariable frame-rate picked-up image, the device comprising settinginformation generation means for generating image pick-up settinginformation which is used to frame-synchronize the image signalgenerated by the image signal generation means of the image pick-updevice with a reference frame, synchronization signal generation meansfor generating the synchronization signal that corresponds to thereference frame, synchronization signal output means for outputting thegenerated synchronization signal with the generated image pick-upsetting information being inserted there into, and control means forsetting the reference frame.

In the present invention, the drive-and-control means drives andcontrols the image signal generation means that generates an imagesignal of a variable frame-rate picked-up image. Further, the settinginformation generation means generates image pick-up information forgenerating an image signal, which is frame-synchronized with thisgenerated image signal. The generated image signal is output from theoutput means with this image pick-up setting information being insertedinto, for example, a blanking interval of the generated image signal.Further, if the image pick-up setting information includes frame rateinformation, a frame rate indicated by the frame rate informationcontained in the image pick-up setting information is set as a framerate of the variable frame-rate picked-up image, starting from its framethat is given first after this image pick-up setting information isoutput, thereby generating the image signal. Further, when a frame rateis instructed according to a read frame rate alteration pattern to varythe frame rate of a variable frame-rate picked-up image, informationindicating the read frame rate alteration pattern is contained in theimage pick-up setting information and also the instructed frame rate isset as the frame rate of the variable frame-rate picked-up image,starting from its frame that is given first after the image pick-upsetting information is output, thus generating the image signal.Furthermore, if a plurality of frame rate instruction means is equippedfor instructing a frame rate of a variable frame-rate picked-up image,priority sequence is set to the plurality of frame rate instructionmeans, so that when more than one frame rate instruction is carried out,frame rate instructed by the frame rate instruction means having thehighest priority is set as the frame rate of the variable frame-ratepicked-up image.

When the image pick-up setting information is input, based on this imagepick-up setting information, the driving operation of image signalgeneration means is controlled so that the generated image signal can beframe-synchronized with an image signal of the reference variableframe-rate picked-up image. If this image pick-up setting informationcontains frame rate information that indicates a frame rate of thereference variable frame-rate picked-up image, a frame rate indicated bythe frame rate information contained in the input image pick-up settinginformation is set as a frame rate of the variable frame-rate picked-upimage, starting from its frame which is given first after the imagepick-up setting information is input, thus generating the image signal.Further, if the image pick-up setting information includes informationfor reading a frame rate alteration pattern, a frame rate instructed onthe basis of the frame rate alteration pattern is set as the frame rateof the variable frame-rate picked-up image, starting from its framewhich is given first after the image pick-up setting information isinput, thus generating the image signal. Furthermore, if prioritysequence is set to a frame rate instructed by the frame rate instructionmeans and a frame rate based on the image pick-up setting informationand when more than one frame rate instruction is carried out, a framerate instructed by the frame rate instruction means having the highestpriority is set as the frame rate of the variable frame-rate picked-upimage, thus generating the image signal.

Further, in the synchronization-signal-generating device, image pick-upsetting information is generated for frame-synchronizing the imagesignal generated by the image pick-up device with the reference frameand a synchronization signal corresponding to the reference frame isgenerated, so that the generated synchronization signal is output withthe image pick-up setting information being inserted into, for example,a blanking interval of the synchronization signal.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a diagram for showing a configuration of an image pick-upsystem;

FIG. 1B is a diagram for showing a configuration of another imagepick-up system;

FIG. 2 is a diagram for showing a configuration of an image pick-updevice;

FIG. 3 is a diagram for showing a relationship of an image pick-up framerate and the number of add frames with respect to a variable frame rate;

FIG. 4A is a diagram for explaining a CDR scheme;

FIG. 4B is a diagram for explaining the CDR scheme;

FIG. 4C is a diagram for explaining the CDR scheme;

FIG. 5 is a diagram for showing a configuration of a signal generationcontrol portion;

FIG. 6A is a diagram for showing one example of a count value of acounter;

FIG. 6B is a diagram for showing another example of the count value of acounter;

FIG. 6C is a diagram for showing further example of the count value of acounter;

FIG. 6D is a diagram for showing still further example of the countvalue of a counter;

FIG. 6E is a diagram for showing additional example of the count valueof each counter;

FIG. 7A is a diagram for explaining an operation of generating an imagesignal in a picked-up image with variable frame-rate;

FIG. 7B is a diagram for explaining the operation of generating theimage signal in the picked-up image with variable frame-rate;

FIG. 7C is a diagram for explaining the operation of generating theimage signal in the picked-up image with variable frame-rate;

FIG. 7D is a diagram for explaining the operation of generating theimage signal in the picked-up image with variable frame-rate;

FIG. 7E is a diagram for explaining the operation of generating theimage signal in the picked-up image with variable frame-rate;

FIG. 7F is a diagram for explaining the operation of generating theimage signal in the picked-up image with variable frame-rate;

FIG. 8A is a diagram for showing operations of the image pick-up devicesof a master side and a slave side;

FIG. 8B is a diagram for showing the operations of the image pick-updevices of the master side and the slave side;

FIG. 8C is a diagram for showing the operations of the image pick-updevices of the master side and the slave side;

FIG. 8D is a diagram for showing the operations of the image pick-updevices of the master side and the slave side;

FIG. 8E is a diagram for showing the operations of the image pick-updevices of the master side and the slave side;

FIG. 8F is a diagram for showing the operations of the image pick-updevices of the master side and the slave side;

FIG. 8G is a diagram for showing the operations of the image pick-updevices of a master side and a slave side;

FIG. 8H is a diagram for showing the operations of the image pick-updevices of the master side and the slave side;

FIG. 8I is a diagram for showing the operations of the image pick-updevices of the master side and the slave side;

FIG. 8J is a diagram for showing the operations of the image pick-updevices of the master side and the slave side;

FIG. 8K is a diagram for showing the operations of the image pick-updevices of the master side and the slave side;

FIG. 8L is a diagram for showing the operations of the image pick-updevices of the master side and the slave side;

FIG. 8M is a diagram for showing the operations of the image pick-updevices of the master side and the slave side;

FIG. 8N is a diagram for showing the operations of the image pick-updevices of the master side and the slave side;

FIG. 9A is a diagram for showing image pick-up setting information;

FIG. 9B is a diagram for showing the image pick-up setting information;

FIG. 9C is a diagram for showing the image pick-up setting information;

FIG. 9D is a diagram for showing the image pick-up setting information;

FIG. 10 is a diagram for showing a count width of an H counter;

FIG. 11 is a diagram for explaining priority sequence of variable framerate setting instructions; and

FIG. 12 is a diagram for showing a configuration of asynchronization-signal-generating device.

BEST MODE FOR CARRYING OUT THE INVENTION

The following will describe one embodiment of the present invention withreference to drawings. FIGS. 1A and 1B each shows a configuration of animage pick-up system that can use a plurality of image pick-up deviceseach capable of varying a frame rate thereof, to frame-synchronize imagesignals generated by these image pick-up devices with each other, FIG.1A of which shows a case where the system is constituted of a pluralityof image pick-up devices 10 only and FIG. 1B of which shows a case whereit is constituted of a synchronization-signal-generating device 50 andthe plurality of image pick-up devices 10.

If no synchronization-signal-generating device 50 is used, the imagepick-up devices 10 are connected as shown in FIG. 1A, one of which isset as a master side image pick-up device so that image signalsgenerated by the slave-side image pick-up devices may beframe-synchronized with an image signal generated by this master-sideimage pick-up device. If the synchronization-signal-generating device 50is used, on the other hand, the image pick-up devices 10 are connectedto the synchronization-signal-generating device 50 as shown in FIG. 1B,so that this synchronization-signal-generating device 50 mayframe-synchronize the image signals generated by the image pick-updevices 10.

FIG. 2 shows a configuration of the image pick-up device 10. On an imagepick-up surface of an image pick-up element (not shown) that constitutesan image pick-up portion 111 in an image signal generation portion 11,an image of a subject is formed on the basis of light which is madeincident upon the surface through an image pick-up lens (not shown). Theimage pick-up element generates image pick-up charge for the image ofsubject through photoelectric transfer and reads the image pick-upcharge based on a drive-and-control signal RC out of a later-describeddrive portion 117 to convert it into a voltage signal. Furthermore, itsupplies this voltage signal as an image picked-up signal Spa to apre-amplification portion 112.

The pre-amplification portion 112 amplifies the picked-up image signalSpa and then performs processing to remove its noise component, forexample, correlated dual sampling. Furthermore, it converts thenoise-removed image signal into a digital signal to perform feedbackclamp processing on it, thereby generating an image signal having adesired magnitude at a stable black level. Furthermore, it performsflare correction to correct a signal level of the image signal inaccordance with a flare quantity. Further, the pre-amplification portion112 performs correction-processing etc. on a defect of the image pick-upelement. The processing by this pre-amplification portion 112 isperformed on the basis of a synchronization signal SYe supplied from thedrive portion 117, to supply a post-processing image signal DVa togetherwith a synchronization signal for this image signal DVa, to apreprocessing portion 113. It is to be noted that, also at thepreprocessing portion 113 as well as later-describedframe-addition-processing portion 114, main-line-picture-processingportion 115, and monitor-picture-processing portion 116, theirprocessing is performed on the basis of each synchronization signal (notshown) which is supplied together with each image signal, and eachpost-processing image signal together with each synchronization signalfor the image signal are supplied to their following processingportions.

The preprocessing portion 113 uses the image signal DVa to performsignal processing operations, for example, white balance adjustment,gain correction, white shading correction, etc. An image signal DVbobtained by this preprocessing portion 113 is supplied to theframe-addition-processing portion 114. The signal processing operationto be performed at the preprocessing portion 113 is set on the basis ofa control signal CTa supplied from an operation control portion 30,which will be described later. Further, when the signal processingoperation is changed by using the control signal CTa from the operationcontrol portion 30, using a decision signal DF supplied from alater-described signal generation control portion 24, this change isreflected after a frame addition period ends at theframe-addition-processing portion 114.

The frame-addition-processing portion 114 performs frame additionprocessing on the image signal DVb to vary a frame rate of the imagesignal DVb. This frame addition processing can be performed using arandom access memory (RAM). For example, to perform 3-frame addition, afirst frame of the image signal DVb is stored in an RAM-1, the signalstored in which is read and added to a second frame of the image signalDVb and stored in an RAM-2. The sum signal stored in this RAM-2 is readand added to a third frame of the image signal DVb and stored in anRAM-3. The signal stored in this RAM-3 thus makes a sum of the threeframes of the image signal DVb, so that by reading this signal andmultiplying its signal level by (⅓), a required signal level isobtained. Further, a fourth frame of the image signal DVb is stored inthe RAM-1, the signal stored in which is read and added to a fifth frameof the image signal DVb and stored in the RAM-2. The sum signal storedin the RAM-2 is read and added to a sixth frame of the image signal DVband stored in the RAM-3. The signal stored in this RAM-3 thus makes asum of the three frames of the image signal DVb, so that by reading thissignal and multiplying its signal level by (⅓), a required signal levelis obtained. Similarly, subsequent three frames of the image signal DVbare added up to sequentially generate an image signal DVc having arequired signal level.

It is to be noted that the frame addition processing can be performedalso using a frame delay circuit. For example, the first frame of theimage signal DVb is delayed by two-frame period through the frame delaycircuit and the second frame of the image signal DVb is delayed by oneframe period through the frame delay circuit. These delayed first frameof the image signal and second frame of the image signal DVb are addedto the third frame of the image signal DVb to obtain a sum of the threeframe of the image signal DVb, a signal level of which is multiplied by(⅓) as described above to obtain an image signal DVc having a requiredsignal level and an original frame rate multiplied by (⅓).

By thus performing the frame addition processing, for example, if aframe rate of the image signal DVb is “60 P” (where the numeralindicates the number of frames per second and P stands for progressivesignal, which holds true also with the other cases) and the number ofadded frames is two, an image signal having a frame rate of “30 P” canbe obtained. If the number of added frames is four, an image signalhaving a frame rate of “15 P” can be obtained.

Furthermore, not only by switching the number of added frames but alsoby controlling signal reading from the image pick-up element so that theframe rate of the picked-up image signal Spa can vary, the frame rate ofthe image signal DVc can be varied continuously.

The image signal DVc of a variable frame-rate picked-up image obtainedat the frame-addition-processing portion 114 is supplied to themain-line-picture-processing portion 115 and themonitor-picture-processing portion 116.

The main-line-picture-processing portion 115 performs process treatmentsuch as γ correction (gamma correction), profile compensationprocessing, and Knee correction, on the image signal DVc supplied fromthe frame-addition-processing portion 114. An image signal DVd obtainedby performing the processing at this main-line-picture-processingportion 115 is supplied to a main line picture output portion 15.

The monitor-picture-processing portion 116 performs process treatment inaccordance with an image display device connected for confirmation ofpicked-up images. For example, if an image is displayed using a cathoderay tube or a liquid crystal display element for confirmation ofpicked-up images, it performs process treatment in accordance with γcharacteristics, gray-scale display characteristics, etc. of the cathoderay tube or the liquid crystal display element. An image signal DVeobtained by performing the processing at this monitor-picture-processingportion 116 is supplied to a monitor picture output portion 16. It is tobe noted that process treatment operations by themain-line-picture-processing portion 115 and themonitor-picture-processing portion 116 are controlled on the basis of acontrol signal CTb from the operation control portion 30.

The main line picture output portion 15 converts the supplied imagesignal DVd into a signal that matches recording equipment etc. connectedto this image pick-up device 10 and outputs it as a signal CAM. Forexample, if equipment that uses a component signal or a composite signalis connected to the pick-up device, it outputs the image signal DVd as asignal CAM that matches respective pieces of equipment. Further, if theimage signal is transmitted via a serial digital interface etc. which isstandardized as SMPTE259M or SMPTE292M, it generates a transmissionsignal in accordance with the interface standard on the basis of theimage signal DVd and outputs it as the signal CAM. Further, if suppliedwith image pick-up setting information IF from a signal generationcontrol portion 24, which will be described later, this image pick-upsetting information IF is output with it being inserted into the signalCAM. For example, the image pick-up setting information IF is outputwith it being inserted into a blanking interval of the signal CAM.Furthermore, the main line picture output portion 15 supplies asynchronization signal SYout for the image signal DVd to a phasecomparison portion 22 and the signal generation control portion 24.

The monitor picture output portion 16 converts the supplied image signalDVe into a signal MNT that matches an image display device forconfirmation of picked-up images and outputs it. For example, if theimage display device uses an analog signal, it converts the image signalDVe into an analog signal, which is then output as a signal MNT.

It is to be noted that by changing over a frame rate (hereinafterreferred to as “image pick-up frame rate”) FRp of the image picked-upsignal Spa generated by the image pick-up portion 111 and the number ofadded frames FA by the frame-addition-processing portion 114, it ispossible to continuously vary a frame rate (hereinafter referred to as“variable frame rate”) FRc of a variable frame-rate picked-up image. Forexample, as shown in FIG. 3, to set the variable frame rate FRc into arange of “60 P≧FRc>30 P”, the number of added frames FA can be set to“1” and the image pick-up frame rate FRp can be equalized to thevariable frame rate FRc. To set the variable frame rate FRc into a rangeof “30 P≧FRc>20 P”, the number of added frames FA can be set to “2” andthe image pick-up frame rate FRp can be set to double the variable framerate FRc. To set the variable frame rate FRc into a range of “20P≧FRc>15 P”, the number of added frames FA can be set to “3” and theimage pick-up frame rate FRp can be set to triple the variable framerate FRc. By similarly changing over the image pick-up frame rate FRpand the number of added frames FA, it is possible to obtain a desiredframe rate of the image signal of a variable frame-rate picked-up image.

To vary the frame rate of the image picked-up signal Spa, controlling acharge accumulation period and an image pick-up charge read timing, etc.at the image pick-up element using the drive-and-control signal RCsupplied from the drive portion 117 to the image pick-up portion 111allows the image picked-up signal Spa with the varied frame rate to beobtained. Furthermore, by varying the image pick-up frame rate FRp byadjusting a length of horizontal or vertical blanking interval on theassumption that the common data rate scheme (CDR: common samplingfrequency scheme) is used, it is possible to generate such an imagepicked-up signal Spa that an image size in a valid screen period doesnot change even if the image pick-up frame rate FRp is varied. Further,by using the CDR scheme, it becomes unnecessary to vary an operatingfrequency of each of the components that use the image pick-up framerate FRp in accordance with the image pick-up frame rate FRp, therebysimplifying the configuration thereof.

According to the CDR scheme, by adjusting a length of the horizontalblanking interval as shown in FIG. 4B or adjusting a length of thevertical blanking interval as shown in FIG. 4C with respect to such animage signal that the blanking interval and the valid screen periods areset as shown in FIG. 4A, it is possible to generate the image picked-upsignal Spa having the varied image pick-up frame rate FRp withoutchanging any image size in the valid screen periods.

A synchronization-separating-processing portion 21 shown in FIG. 2, whensupplied with an image signal of a reference variable frame-ratepicked-up image having a synchronization signal SYref which correspondsto the reference frame from the synchronization-signal-generating device50 or a synchronization signal SYref from any other image pick-updevices 10, separates a horizontal synchronization signal HDref from thesynchronization signal SYref and supplies it to the phase comparisonportion 22. Furthermore, if the supplied signal contains image pick-upsetting information IFex, it extracts the image pick-up settinginformation IFex and supplies the information to the signal generationcontrol portion 24 and the operation control portion 30. Furthermore, itgenerates an information latch signal LCifex for latching a count valuecontained in the image pick-up setting information IFex. This imagepick-up setting information IFex is used to frame-synchronize an imagesignal generated by the image pick-up device that is supplied with theimage pick-up setting information IFex with an image signal of areference variable frame-rate picked-up image generated by the imagepick-up device which supplies the image pick-up setting information IFexor a reference frame set by the synchronization-signal-generating device50.

The phase comparison portion 22 determines a difference in phase betweena horizontal synchronization signal HDout contained in thesynchronization signal SYout supplied from the main line picture outputportion 15 and the horizontal synchronization signal HDref supplied fromthe synchronization-separating-processing portion 21, to control afrequency of an oscillated signal MC generated by a voltage-controlledoscillator (VCO) 23 so that this phase difference may be nil. It is tobe noted that if the horizontal synchronization signal HDref is notsupplied from the synchronization-separating-processing portion 21, theVCO 23 is permitted to run for itself.

The signal generation control portion 24, which serves asdrive-and-control means and setting information generation means, usesthe oscillated signal MC generated by the VCO 23, to count based oncounter setting information STc supplied from the operation controlportion 30. It further utilizes a count result to generate a timingsignal PT and a synchronization signal SYd for driving the image pick-upportion 111 and supply them to the drive portion 117. It is to be notedthat if the synchronization signal SYref is supplied, it is possible togenerate the synchronization signal SYd in such a manner that it may goahead of the synchronization signal SYref by as much as a difference inphase between the synchronization signals SYout and SYd, therebysynchronizing the synchronization signal SYout with the synchronizationsignal SYref.

Furthermore, the signal generation control portion 24 generates a pulsesignal CRW for controlling, for example, writing of an image signal toand reading of it from the RAM so that the frame-addition-processingportion 114 can add the image signal DVb as much as the number of addedframes in order to obtain the image signal DVc. Further, when frameaddition processing is performed in the frame-addition-processingportion 114, it generates such a decision signal DF as to indicate arelevant frame addition period and supplies the signal to thepreprocessing portion 113.

By thus generating the timing signal PT and the synchronization signalSYd and supplying them to the drive portion 117 and also generating thepulse signal CRW and supplying it to the frame-addition-processingportion 114, the frame rate FRp of the image picked-up signal Spa andthe frame addition processing are controlled so that an image signal ofthe variable frame-rate picked-up image generated by the image signalgeneration portion 11 may have a frame rate set by the operation controlportion 30.

Further, if the image pick-up device is set as a master side one, thesignal generation control portion 24 uses an image signal of a variableframe-rate picked-up image generated by this master side image pick-updevice as an image signal of a reference variable frame-rate picked-upimage to generate the image pick-up setting information IF for causing aslave side image pick-up device to generate an image signal which isframe-synchronized with this image signal and supply this image pick-upsetting information IF to the main line picture output portion 15. Thisimage pick-up setting information IF is generated by using a count valueobtained through counting and frame rate setting information SFRsupplied from the operation control portion 30.

If the image pick-up device is set as a slave side image pick-up deviceand the image pick-up setting information IFex is supplied from a masterside image pick-up device, on the other hand, the timing signal PT, thepulse signal CRW, etc. are generated on the basis of this image pick-upsetting information IFex to cause the main line picture output portion15 to output an image signal which is frame-synchronized with an imagesignal of a reference variable frame-rate picked-up image generated bythe master side image pick-up device.

FIG. 5 shows a configuration of the signal generation control portion.The counter setting information STc supplied from the operation controlportion 30 is supplied to a counter setting latch portion 241. The framerate setting information SFR supplied from the operation control portion30, on the other hand, is supplied to an image pick-up settinginformation latch portion 248.

The counter setting latch portion 241 latches the counter settinginformation STc based on a setting latch signal LCa supplied from alatch signal generation portion 247, which will be described later. Tothis counter setting latch portion 241, an H counter 242, a V counter243, an added frame counter 244, an image pick-up frame counter 245, andan output frame counter 246 are connected. The counter settinginformation STc is comprised of setting information that sets a countwidth of each of the counters, to set each counter's count width basedon the latched counter setting information STc.

The H counter 242 counts the number of horizontal pixels based on theoscillated signal MC supplied from the VCO23 and supplies a count valueHct to the image pick-up setting information latch portion 248 and apulse signal generation portion 249. Further, the H counter 242 has itscount width set to the number of horizontal pixels for one horizontalscan period based on the counter setting information STc and, uponcompletion of counting of the horizontal pixels for one horizontal scanperiod, resets the count value Hct and supplies the V counter 243 with asignal HP indicating that the one horizontal scan period has ended.

The V counter 243 counts the number of scan lines by using the signal HPand supplies a count value Vct to the image pick-up setting informationlatch portion 248 and the pulse signal generation portion 249. Further,the V counter 243 has its count width set to the number of scan linesfor one frame period based on the counter setting information STc and,upon completion of counting of the scan lines for one frame period,resets the count value Vct and supplies a signal VP indicating that theone frame period has ended, to the added frame counter 244, the imagepick-up frame counter 245, and the latch signal generation portion 247.

The added frame counter 244 counts the number of image picked-up framesby using the signal VP and supplies a count value Fmct to the imagepick-up setting information latch portion 248 and the pulse signalgeneration portion 249. Further, the added frame counter 244 has itscount width set to the number of added frames based on the countersetting information STc and, upon completion of counting of frames forthe number of added frames FA, resets the count value Fmct and suppliesa signal FMP indicating that the one addition period has ended, to theoutput frame counter 246 and the latch signal generation portion 247.

The image pick-up frame counter 245 counts image picked-up frames byusing the signal VP. The image pick-up frame counter 245 has its countwidth set to a value of the image pick-up frame rate FRp based on thecounter setting information STc and, upon completion of counting offrames for the image pick-up frame rate FRp, resets the count value Fpctand supplies the output frame counter 246 with a signal FPP indicatingthat a period for the image pick-up frame rate FRp has ended.

The output frame counter 246 counts the number of times the additionperiod has been encountered by using the signal FMP and, when it hasdecided on the basis of the signal FPP that a period for the imagepick-up frame rate FRp has ended, resets the count values and outputs acount reset signal RES that resets the count values of the othercounters.

The latch signal generation portion 247, based on the signals VP and FMPand at timing when frames for one addition period end, generates thesetting latch signal LCa that causes the counter setting latch portion241 to latch the counter setting information STc.

The image pick-up setting information latch portion 248 generates aninformation latch signal LCif (not shown) and, at latch timing indicatedby this information latch signal LCif, latches the count values Hct,Vct, and Fmct and the frame rate setting information SFR and suppliesthem as the image pick-up setting information IF in a predeterminedformat to the main line picture output portion 15. For example, theinformation latch information LCif is generated with ID respect to thesynchronization signal SYout, to generate the image pick-up settinginformation IF and supply it to the main line picture output portion 15so that the image pick-up setting information IF may be inserted to apredetermined position in the blanking interval. By thus determining theinsertion position of the image pick-up setting information IF, theimage pick-up setting information IF can be easily extracted from thesignal CAM.

The pulse signal generation portion 249 generates the timing signal PT,the synchronization signal SYd, the pulse signal CRW, and the decisionsignal DF based on the count values Hct, Vct, and Fmct and theoscillated signal MC.

A count latch portion 250, when supplied with the image pick-up settinginformation IFex from the synchronization-separating-processing portion21, latches count values Hctex and Vctex contained in the image pick-upsetting information IFex and resets a count value of the H counter 242and that of the V counter 243 to the count values Hctex and Vctex,respectively. This count latch portion 250 latches them at timing ofinserting the image pick-up setting information IFex to the position,based on the information latch signal LCifex.

Further, if the timing when the count values Hct and Vct are latched sothat the master side image pick-up device may generate the image pick-upsetting information IF does not agree with the timing when the slaveside image pick-up device resets the H counter 242 and the V counter 243to the count values Hctex and Vctex, respectively, that is, if thesetimings do not agree because of a lapse of time required by formattingor decoding of the image pick-up setting information IF, count valuesHexct and Vexct are offset by as much as a difference in timing phaseand supplied to the H counter 242 and the V counter 243, respectively.Thus, offsetting the count values Hexct and Vexct by as much as thedifference in timing phase allows the H counter 242 and the V counter243 of the slave side image pick-up device to be synchronized with the Hcounter 242 and the V counter 243 of the master side image pick-updevice.

FIGS. 6A-6E each show one example of a count value of each counter inthe signal generation control portion. If the variable frame rate FRc isset to “18 P”, the number of added frames FA is “3” and the imagepick-up frame rate FRp is “54 P” as shown in FIG. 3. Therefore, thecount value Fpct repeats itself in a range of “0-53”, the count valueFmct repeats itself in a range of “0-2” and a count value Rct repeatsitself in a range of “0-17”. Further, if the number of pixels per lineis 2200 and the number of scan lines is 1125, the count value Vctrepeats itself in a range of “0-1124”. Furthermore, when the length of ahorizontal blanking interval is adjusted in accordance with the CDRscheme, the count value Hct repeats itself in a range of “0-2439”, whichis larger than the number of pixels, so that the image pick-up framerate FRp may be “54 P”.

The drive portion 117 shown in FIG. 2 generates the drive-and-controlsignal RC for driving the image pick-up element and supplies it to theimage pick-up portion 111 based on the synchronization signal SYd thussupplied. Further, driving the image pick-up element based on the timingsignal PT in accordance with the CDR scheme allows the frame rate of theimage picked-up signal Spa to vary. Furthermore, the synchronizationsignal SYe for the image picked-up signal Spa is generated and suppliedto the pre-amplification portion 112.

To the operation control portion 30, a user interface portion 31 isconnected. When supplied with an operation signal PSa in accordance witha user operation through this user interface portion 31, the operationcontrol portion 30 generates the control signals CTa and CTb based onthis operation signal PSa, to control operations of the preprocessingportion 113, the main-line-picture-processing portion 115, and themonitor-picture-processing portion 116. Further, it supplies the countersetting information STc to the signal generation control portion 24 tocontrol counting so that the image signal DVc having a desired framerate may be generated. Furthermore, it supplies the frame rate settinginformation SFR to the signal generation control portion 24. Further,when supplied with the image pick-up setting information IFex from thesynchronization-separating-processing portion 21, it generates thecounter setting information STc based on this image pick-up settinginformation IFex.

Further, the image pick-up device 10 can insert the image pick-upsetting information IFex supplied to itself into a blanking interval ofthe signal CAM and supply it to the subsequent-stage image pick-updevice or supply the synchronization signal SYref supplied to itself tothe subsequent-stage image pick-up device, thereby easily generatingsuch an image signal as to have been frame-synchronized among the imagepick-up devices even if the plurality of image pick-up devices isconnected in a daisy chain.

Next, the following will describe operations for generating an imagesignal of a variable frame-rate picked-up image in the image pick-updevice. FIGS. 7A-7F show a case where the frame-addition-processingportion 114 performs frame addition processing by using RAM-1 throughRAM-3, an adder, etc. For example, if the variable frame rate FRc is “18P”, the variable frame rate FRp is “54 P” and the number of added framesFA is “3” from FIG. 3. It is to be noted that FIG. 7A shows a frame ofthe image signal DVb, FIG. 7B shows an operation of RAM-1 in theframe-addition-processing portion 114, FIG. 7C shows an operation ofRAM-2 therein, FIG. 7D shows an operation of RAM-3 therein, and FIG. 7Eshows a frame of the image signal DVc.

At time point t1, when frame “0f” of the image signal DVb starts, theframe-addition-processing portion 114 sets, for example, RAM-1 as awrite RAM and stores the image signal DVa of frame “0f” in the writeRAM.

At time point t2, when a frame of the image signal DVc starts, threeframes of the image signal are not completely added up yet, so that theimage signal DVc is rendered as a blank frame.

At time point t3, when frame “0f” of the image signal DVb ends and frame“1f” starts, RAM-1 where the image signal of frame “0f” is stored isspecified as an internal read RAM and the write RAM is changed over fromRAM-1 to, for example, RAM-2. Furthermore, the signal stored in theinternal read RAM, that is, the signal of frame “0f” stored in RAM-1 isread and added to the image signal DVa of frame “1f” by the adder andstored in RAM-2, which is the write RAM.

At time point t4, when frame “1f” of the image signal DVb ends and frame“2f” starts, to generate a three-frame addition signal, RAM-2 in whichthe sum signal of frames “0f” and “1f” is written is specified as theinternal read RAM. Further, the write RAM is changed over from RAM-2 to,for example, RAM-3. Furthermore, the signal stored in the internal readRAM, that is, the signal stored in RAM-2 is read and added to the imagesignal DVb of frame “2f” by the adder and stored in the RAM-3, which isthe write RAM.

At time point t5, when frame “2f” of the image signal DVb ends and frame“3f” starts, the three-frame addition signal obtained by adding up threeframes of the image signal DVb is generated completely, so that theRAM-3 in which this three-frame addition signal is stored is specifiedas an external read RAM. Further, RAM-1 is set as the write RAM, tostore the image signal DVa of frame “3f” in the write RAM.

When the three-frame addition signal is generated and then a frame ofthe image signal DVc is timed to start, for example, at time point t6when the frame of the image signal DVc starts, the three-frame additionsignal is read out of the external read RAM and has its signal levelmultiplied by (⅓) and is output as the image signal DVc. Further, theframe of the image signal DVc generated by reading the three-frameaddition signal out of the external read RAM is supposed to be indicatedby an identify signal DJ shown in FIG. 7F as a frame of a variableframe-rate picked-up image. It is to be noted that if the three-frameaddition signal is not completely written to the RAM yet or if thethree-frame addition signal is read completely but the next three-frameaddition signal cannot be read, no new frame of the new picked-up imagecan be generated. In this case, by repeating a frame of a picked-upimage having a variable frame rate, a frame (blank frame) having noimage signal of the picked-up image is avoided from being provided inthe image signal DVc. Further, this frame is made of a repeated frame ofthe picked-up image with the variable frame rate and so rendered invalidby the identify signal DJ. It is to be noted that a blank frame, if any,is also rendered invalid. By thus generating the identify signal DJ, itis possible to decide a frame of a picked-up image having a variableframe rate by using the identify signal DJ. That is, by selecting animage signal of a frame decided valid by the identify signal DJ, it ispossible to select the image signal of a variable frame-rate picked-upimage.

Similarly, by using RAM-1 through RAM-3, the adder, etc. to add up threeframes of the image signal DVb so that a three-frame addition signal maybe generated and reading this three-frame addition signal at timing whena frame of the image signal DVc starts, it is possible to obtain theimage signal DVc in which a valid frame is contained at the variableframe rate FRc. That is, as shown in FIG. 7E, it is possible to generatethe image signal DVc that contains a frame which is valid at a desiredvariable frame rate “18 P”, which is a recording frame rate (e.g., “60P”) corresponding to the device to which signal CAM is supplied. It isto be noted that if a signal having the signal level of the three-frameaddition signal multiplied by (⅓) is stored in a memory and read at aframe rate of 18 P, of course it can be a signal having a frame rate of18 P.

By reproducing a picked-up image having the thus obtained variable framerate FRc at a predetermined reproduction frame rate, it is possible toeasily obtain fast reproduction images and slow reproduction images. Forexample, if the reproduction frame rate is “24 P” and when the variableframe rate FRc is set to “24 P” in image pick-up, motion of a subject ina reproduced image has the same speed as the physical subject. If thevariable frame rate FRc is set higher than “24 P” in image pick-up, onthe other hand, the number of frames generated in a unit time increases,so that the speed of the motion of the subject in the reproduced imagedecreases. Furthermore, if the variable frame rate FRc is set lower than“24 P” in image pick-up, the number of frames generated in a unit timedecreases, so that the speed of the motion of the subject in thereproduced image increases. By thus varying the variable frame rate FRc,it is possible to display the subject moving at speeds different from anactual speed, thereby easily obtaining special video effects.

Next, the following will describe operations for connecting a pluralityof image pick-up devices to each other to frame-synchronize imagesignals generated by these image pick-up devices with each other. OfFIGS. 8A-8N, FIG. 8A-8G each show an operation of the master side imagepick-up device and FIGS. 8H-8N each show an operation of the slave sideimage pick-up device.

FIG. 8A shows setting condition of the variable frame rate FRc in themaster side image pick-up device; FIG. 8B shows the count value Vct;FIG. 8C shows the count value Fmct; FIG. 8D shows the count value Fpct;FIG. 8E shows the count value Rct; FIG. 8F shows the setting latchsignal Lca; and FIG. 8G shows the information latch signal LCif forlatching the image pick-up setting information IF generated by the imagepick-up setting information latch portion 248. Further, FIG. 8H showssetting condition of the variable frame rate FRc in the slave side imagepick-up device; FIG. 8I shows the information latch signal Lcifex; FIG.8J shows the count value Vct; FIG. 8K shows the count value Fmct; FIG.8L shows the count value Fpct; FIG. 8M shows the count value Rct; andFIG. 8N shows the setting latch signal LCa.

At time point t11, when the information latch signal LCif indicates alatch timing, the image pick-up setting information latch portion 248latches a count value from the counter and the frame rate settinginformation SFR from the operation control portion 30 and supplies thislatched information to the main line picture output portion 15 as theimage pick-up setting information IF. The main line picture outputportion 15 inserts this image pick-up setting information IF into thesignal CAM and outputs it.

FIGS. 9A-9D show the image pick-up setting information IF inserted intothe signal CAM. It is to be noted that if the image pick-up settinginformation IF is large in amount, it is divided into a plurality oflines in a vertical blanking interval and inserted as shown in FIG. 9A.For example, in a first line, the image pick-up frame rate FRp and thecount value Vct are inserted as shown in FIG. 9B. In a second line, thecount value Fmct and the count value Hct are inserted as shown in FIG.9C. In a third line, the number of added frames FA is inserted as shownin FIG. 9D. It is to be noted that to each piece of the information,parity PA is added for error detection.

Furthermore, each of the lines is provided with a flag EN indicatingwhether to validate or invalidate the information. Further, the firstline is provided with a scheme decision flag P/I indicating which one ofinterlace and progressive schemes is employed, an output set flag ORindicating whether the signal CAM is constituted of a signal with aframe rate of 60 P into which an image signal of a picked-up image inaccordance with the variable frame rate FRc is contained or of a signalwith a frame rate of 30 P into which an image signal of a picked-upimage in accordance with the variable frame rate FRc is contained (theoutput set flag OR may be arranged to indicate whether the frame rate is48 P or 24 P), pattern operation information TR to which one or aplurality of frame rate alternation patterns is (are) set beforehand sothat these set frame rate alteration patterns may be read to vary theframe rate, etc. By providing such the information, it is possible toeasily change the frame rate automatically by using a variety ofpatterns. Alternatively, the count value Fpct may be supplied from theimage pick-up frame counter 245 to the image pick-up setting informationlatch portion 248, to contain the count value Fpct in the image pick-upsetting information IF as shown in FIG. 9B. Further, if the imagepick-up device capable of switching a horizontal image size is used as amaster side image pick-up device and a slave side one, horizontal imagesize information HW is to be contained in the image pick-up settinginformation IF as shown in FIG. 9D. In this case, the horizontal imagesize of the slave side image pick-up device can be matched with that ofthe master side image pick-up device.

At time point t11 shown in FIGS. 8A-8N, the slave side image pick-updevice extracts the inserted image pick-up setting information IF fromthe signal CAM output from the master side image pick-up device by thesynchronization-separating-processing portion 21 and supplied as theimage pick-up setting information IFex to the signal generation controlportion 24 and the operation control portion 30. Further, based on asynchronization signal for the signal CAM, the information latch signalLCifex for latching a count value contained in the image pick-up settinginformation IFex is generated by thesynchronization-separating-processing portion 21 and supplied to thesignal generation control portion 24.

The count latch portion 250 in the signal generation control portion 24latches the count values Hctex and Vctex contained in the image pick-upsetting information IFex, based on the information latch signal LCifex.This latched count value Hctex is supplied to the H counter 242 to reseta count value of the H counter 242 to the count value Hctex. The latchedcount value Vctex, on the other hand, is supplied to the V counter 243to reset a count value of the V counter 243 to the count value Vctex. Itis to be noted that as described above, if there occurs a difference inphase between timing when the count values Hct and Vct are latched togenerate the image pick-up setting information IF at the master sideimage pick-up device and timing when the H counter 242 and the V counter243 are reset to the count values Hctex and Vctex, respectively, at theslave side image pick-up device, the count values Hctex and Vctex areoffset by as much as this difference in phase. By thus offsetting thecount values Hctex and Vctex, it is possible to synchronize the Hcounter 242 and the V counter 243 of the master side image pick-updevice and the slave side image pick-up device. That is, it is possibleto match frame timing between the master side image pick-up device andthe slave side image pick-up device. It is to be noted that if the countvalue Fpct is contained in the image pick-up setting information IF,image pick-up frame counter 245 also can be synchronized, so that it ispossible to match the number of picked-up image frames in the masterside image pick-up device and that in the slave side image pick-updevice with each other.

Next, at time point t12, when the variable frame rate is set to “18 P”,as described above, the image pick-up frame rate FRp is “54 P” and thenumber of added frames FA is “3”. Therefore, the operation controlportion 30 sets the count width of the added frame counter 244 to “3”,the count width of the image pick-up frame counter 245 to “54”, thecount width of the output frame counter 246 to “18”, and the imagepick-up frame rate FRp to “54 P” by adjusting the length of thehorizontal blanking interval in accordance with the CDR scheme, so thatit generates the counter setting information STc that sets the countwidth of the H counter 242 to “2440” and supplies the information to thecounter setting latch portion 241. It is to be noted that if the numberof scan lines for each frame interval is fixed, the count width of the Hcounter 242 is fixed to a value that corresponds to the number of scanlines. Further, to vary the image pick-up frame rate FRp by switchingthe number of scan lines or adjusting the length of the verticalblanking interval, the counter setting information STc that sets thecount width of the V counter 243 in accordance with the number of scanlines and the image pick-up frame rate is generated and supplied to thecounter setting latch portion 241. Further, the frame rate settinginformation SFR that has the image pick-up frame rate FRp and the numberof added frames FA when the variable frame rate FRc is set to “18 P” issupplied to the image pick-up setting information latch portion 248.

It is to be noted that since the count widths of the added frame counter244, the image pick-up frame counter 245, and the output frame counter246 are based on the variable frame rate FRc, the image pick-up framerate FRp, and the number of added frames FA as described above, they canbe determined easily when the variable frame rate FRc is set. Further,since the count width of the H counter 242 is determined in accordancewith the image pick-up frame rate FRp which is set by adjusting thenumber of per-line pixels and the length of the horizontal blankinginterval through the CDR scheme, it is possible to easily generate thecounter setting information STc by holding a table having a count widthof the H counter 242 with respect to the variable frame rate FRc or theimage pick-up frame rate FRp beforehand as shown in FIG. 10 so that itmay be read as required.

At time point t13, when the information latch signal LCif indicates alatch timing, similarly at time point t11, the image pick-up settinginformation IF is inserted into the signal CAM and output. This imagepick-up setting information IF is used to notify the slave side imagepick-up device that the variable frame rate FRc has been set to “18 P”.

At time point t13, further, similarly at time point t11, the slave sideimage pick-up device uses the synchronization-separating-processingportion 21 to extract the image pick-up setting information IFex fromthe signal CAM output from the master side image pick-up device andsupplies it to the signal generation control portion 24 and theoperation control portion 30. Further, it generates the informationlatch signal LCifex based on the synchronization signal for the signalCAM and supplies the signal to the signal generation control portion 24so that the H counter 242 and the V counter 243 in the signal generationcontrol portion 24 may be synchronized with the H counter 242 and the Vcounter 243 in the master side image pick-up device, respectively.

Furthermore, the operation control portion 30 in the slave side imagepick-up device, similar to the mater side image pick-up device,generates the counter setting information STc based on the image pick-upframe rate FRp and the number of added frames FA contained in thesupplied image pick-up setting information IFex and supplies it to thecounter setting latch portion 241.

Then, at time point t14, when a frame addition period ends in the masterside image pick-up device and the setting latch signal LCa is suppliedfrom the latch signal generation portion 247 in the signal generationcontrol portion 24 to the counter setting latch portion 241 therein, thecounter setting information STc supplied from the operation controlportion 30 is latched. This latched counter setting information STc issupplied to the H counter 242, the added frame counter 244, the imagepick-up frame counter 245, and the output frame counter 246, so that thecount width of each of the counters is set in accordance with thevariable frame rate FRc. Therefore, the count value Hvt of the H counter242 repeats itself in a range of “0-2439”, the count value Fmct of theadded frame counter 244 repeats itself in a range of “0-2”, the countvalue Fpct of the image pick-up frame counter 245 repeats itself in arange of “0-53”, and the count value Rct of the output frame counter 246repeats itself in a range of “0-17”, thus starting an operation togenerate the image signal with the variable frame rate FRc as set to “18P”. It is to be noted that the count value Hvt of the V counter 243refers to a count value of the scan lines per frame.

Similarly, in the slave side image pick-up device also, at time pointt14, when a frame addition period ends and the setting latch signal LCais supplied from the latch signal generation portion 247 in the signalgeneration control portion 24 to the counter setting latch portion 241therein, the counter setting information STc supplied from the operationcontrol portion 30 is latched. This latched counter setting informationSTc is supplied to the H counter 242, the added frame counter 244, theimage pick-up frame counter 245, and the output frame counter 246, sothat the count width of each of the counters is set in accordance withthe variable frame rate FRc. Therefore, as in the case of the masterside image pick-up device, the count value Hvt of the H counter 242repeats itself in a range of “0-2439”, the count value Fmct of the addedframe counter 244 repeats itself in a range of “0-2”, the count valueFpct of the image pick-up frame counter 245 repeats itself in a range of“0-53”, and the count value Rct of the output frame counter 246 repeatsitself in a range of “0-17”, thus starting an operation to generate theimage signal with the variable frame rate FRc as set to “18 P”. It is tobe noted that the count value Hvt of the V counter 243 is the same asthat for the master side image pick-up device.

Next, at time point t15, when the variable frame rate FRc is changed to“13 P”, this changed variable frame rate FRc is posted from the masterside image pick-up device to the slave side image pick-up device at timepoint t16. Further, at time point t17, when the frame addition periodends, the count width of each of the counters is changed, so that anoperation at this changed variable frame rate FRc is started by both ofthe master side image pick-up device and the slave side image pick-updevice simultaneously.

The image pick-up setting information IF is thus supplied from themaster side image pick-up device to the slave side image pick-up device,so that operations of the slave side image pick-up device are set on thebasis of this image pick-up setting information IF. Therefore, an imagesignal of a variable frame-rate picked-up image generated by the slaveside image pick-up device is frame-synchronized with an image signal ofa reference variable frame-rate picked-up image generated by the masterside image pick-up device. Furthermore, even if the variable frame ratevaries, frame-synchronized condition is maintained because thisvariation is synchronously performed in the master side and slave sideimage pick-up devices.

Further, if the scheme decision flag P/I indicating which one ofinterlace and progressive schemes is employed is contained in the imagepick-up setting information IF, these schemes can be accommodated easilyby holding information such as the image pick-up frame rate FRp, thenumber of added frames FA, and the count width of the H counter for thevariable frame rate in condition with the information corresponding toeach of the schemes.

If the pattern operation information TR is contained therein, on theother hand, the master side and slave side image pick-up devices canautomatically vary the variable frame rate as synchronized therebetween,thereby improving operability of the image pick-up devices. In thiscase, the same frame rate alteration pattern is held in the master sideand slave side image pick-up devices beforehand. For example, one or aplurality of piece(s) of frame rate alteration pattern information eachfor indicating the variable frame rate FRc which is set as image pick-uptime elapses is generated and held in the operation control portion 30or a memory (not shown) in each of the master side and slave side imagepick-up devices. It is to be noted that by transferring frame ratealteration pattern information to be used from the image pick-up devicethat holds this information to the image pick-up device that does nothave it before image pick-up starts, it is possible to hold the sameframe rate alteration pattern information in a plurality of imagepick-up devices that are connected.

If a held frame rate alteration pattern is read and a frame rate isinstructed in accordance with this read frame rate alteration pattern tovary a frame rate of a variable frame-rate picked-up image, the masterside image pick-up device outputs information that indicates the readframe rate alteration pattern as the pattern operation information TRwith it being contained in the image pick-up setting information IF.Furthermore, pieces of counter setting information STc in accordancewith variable frame rates indicated by the frame rate alteration patternare sequentially generated and supplied to the counter setting latchportion 241. The slave side image pick-up device, if pattern operationinformation TR is contained in the image pick-up setting information IF,reads a frame alteration pattern that corresponds to the patternoperation information TR, sequentially generates counter settinginformation pieces STc in accordance with variable frame rates indicatedby this read frame rate alteration pattern, and supplies them to thecounter setting latch portion 241. In this case, a frame rate indicatedby the frame alteration pattern is set as a frame rate of a variableframe-rate picked-up image to drive the image signal generation portion11 starting from such a frame of the variable frame-rate picked-up imageas to be given first after the image pick-up setting information IF isoutput from the master side image pick-up device or starting from such aframe of the variable frame-rate picked-up image as to be given firstafter the image pick-up setting information IF is input into the slaveside image pick-up device. Therefore, the variable frame rate FRc ischanged as synchronized between the master side and slave side imagepick-up devices, so that these devices can generate such image signalsthat a frame rate of a variable frame-rate picked-up image isautomatically changed in condition where their frames are synchronizedwith each other.

It is to be noted that instruction to set a variable frame rate FRc inthe master side and slave side image pick-up devices is not limited to acase where it is performed on the basis of the above-described imagepick-up setting information IF but can be performed also by a menuoperation signal from an electronic viewfinder (EVF) 70, aremote-control signal from a remote-control device 80, a control signalfrom a camera control device 90, etc.

Therefore, the operation control portion 30 sets priority sequence toinstructions to set the variable frame rate FRc so that the variableframe rate FRc may be set in accordance with the priority sequence. Forexample, it gives priority to the remote control-signal from theremote-control device 80 over the menu operation signal from theelectronic viewfinder 70. Further, the image pick-up setting informationIF is given priority over the remote-control signal. Furthermore, thecontrol signal from the camera control device 90 is given priority overthe image pick-up setting information IF. By thus allocating thepriorities, the image pick-up devices can be operated properly even ifthe plurality of instructions to set the variable frame rate FRc isgiven simultaneously.

Further, it may be arranged that if a setting instruction having higherpriority has ended, a variable frame rate FRc at the time of the endingis held or the variable frame rate FRc is returned to condition beforethe setting instruction having the higher priority is performed. Forexample, if the image pick-up setting information IF is supplied whenthe variable frame rate FRc is being set by the menu operation signalfrom the electronic viewfinder 70, such a variable frame rate FRc as tobe indicated by the image pick-up setting information IF is set. Then,when the supply of the image pick-up setting information IF ends, avariable frame rate FRc at the time of the ending of the supply is held.Alternatively, it may be recovered to a variable frame rate FRc, whichhas been set by the menu operation signal. In such a manner, a varietyof operations can be performed by controlling the variable frame rateFRc.

Further, although the above embodiment has been described with referenceto a case where an image signal of a variable frame-rate picked-up imagegenerated by the slave side image pick-up device is frame-synchronizedwith an image signal of a variable frame-rate picked-up image generatedby the master side image pick-up device, the image signals generated bythe image pick-up devices 10 can be frame-synchronized with each otherby the synchronization-signal-generating device 50 as shown in FIG. 1B.In this case, the synchronization-signal-generating device 50 insertsthe image pick-up setting information IF into a referencesynchronization signal SYref and supplies it to these image pick-updevices 10.

FIG. 12 shows a configuration of the synchronization-signal-generatingdevice. It is to be noted that components of FIG. 12 that correspond tothose of FIG. 5 are indicated by the same reference symbols and detaileddescription of them will be omitted. To a control portion 51 a userinterface portion 52 is connected, so that the control portion 51generates the counter setting information STc and the frame rate settinginformation SFR in accordance with a variable frame rate FRc indicatedby an operation signal PSb from a user interface. It further suppliesthe generated counter setting information STc to the counter settinglatch portion 241 in a signal generation control portion 24 a, whichserves as setting information generation means and synchronizationsignal generation means. Further, it supplies the frame rate settinginformation SFR to the image pick-up setting information latch portion248.

An oscillation portion 53 generates the oscillated signal MC andsupplies it to the H counter 242 and the synchronization signalgeneration portion 251. The synchronization signal generation portion251 generates a synchronization signal SYz based on a count value ofeach counter and the oscillated signal MC to set a reference frame,which provides a reference for each of the image pick-up devices 10.This generated synchronization signal SYz is supplied to asynchronization signal output portion 54. Further, the synchronizationsignal generation portion 251 generates an information latch signal LCzwhose latch timing is an insertion position of the image pick-up settinginformation IF which is set with respect to the synchronization signalSYz and supplies it to an image pick-up setting information latchportion 248 a.

The image pick-up setting information latch portion 248 a latches thecount values Hct, Vct, and Fmct and the frame rate setting informationSFR at latch timing indicated by the information latch signal LCz andsupplies them to the synchronization signal output portion 54 as theimage pick-up setting information IF in a predetermined format.

The synchronization signal output portion 54 inserts the image pick-upsetting information IF into the synchronization signal SYz supplied fromthe synchronization signal generation portion 251 and supplies thesynchronization signal SYref that corresponds to the reference frame toeach of the image pick-up devices.

By thus supplying, from the synchronization-signal-generating device 50,each of the image pick-up devices with the synchronization signal SYrefinto which the image pick-up setting information IF is inserted, thesame operation as the above-described slave side image pick-up devicesis performed at each of the image pick-up devices, so that an imagesignal of a variable frame-rate picked-up image which isframe-synchronized with the reference frame can be output from each ofthe image pick-up devices.

In such a manner, image signals of variable frame-rate picked-up imagescan be generated by the plurality of image pick-up devices in conditionwhere they are frame-synchronized with each other, so that by picking upimages of a subject in different directions using a plurality of imagepick-up devices, it is possible to easily obtain such a plurality ofreproduced fast images or slow images that the subject's motions aresynchronized with each other and the images are picked up in thedifferent directions. Further, these image signals areframe-synchronized with each other, thereby facilitating editingprocessing.

According to the present invention, the device comprises image signalgeneration means for generating an image signal of a variable frame-ratepicked-up image, drive-and-control means for driving and controlling theimage signal generation means, setting information generation means forgenerating image pick-up setting information to generate an image signalwhich is frame-synchronized with the image signal generated by the imagesignal generation means, and output means for outputting the imagesignal generated by the image signal generation means and the imagepick-up setting information. Therefore, controlling the generation ofthe image signal based on the output image pick-up setting informationallows the image signal to be generated with this image signal beingframe-synchronized with the image signal into which the image pick-upsetting information is inserted.

Further, frame rate information is contained in the image pick-upsetting information, so that starting from such a frame of a variableframe-rate picked-up image as to be given first after this image pick-upsetting information is output, a frame rate indicated by the frame rateinformation contained in this output image pick-up setting informationis set as a frame rate of the variable frame-rate picked-up image, todrive the image signal generation means. Therefore, it is possible tovary the frame rate of a variable frame-rate picked-up image insynchronization with the image pick-up device that is supplied with theimage pick-up setting information.

Further, containing, in image pick-up setting information, informationof a scan line position and a pixel position of an image signal to begenerated allows the scan line position and the pixel position of theimage signal generated by the image pick-up device that is supplied withthe image pick-up setting information, to be synchronized. Further, ifholding means for holding a frame rate alteration pattern is providedand when the frame rate alteration pattern held in the holding means isread and a frame rate that corresponds to this read frame ratealteration pattern is instructed, to vary a frame rate of a variableframe-rate picked-up image, information indicating the read frame ratealteration pattern is contained in the image pick-up setting informationand, starting from such a frame of a variable frame-rate picked-up imageas to be given first after this image pick-up setting information isoutput, the instructed frame rate is set as the frame rate of thevariable frame-rate picked-up image, to generate an image signal. It isthus possible to change frame rates of image signals generated by theimage pick-up devices supplied with the image pick-up settinginformation in condition where they are synchronized with each other.Furthermore, the plurality of frame rate instruction means forinstructing a frame rate of a variable frame-rate picked-up image andthe operation control means for setting priority sequence to theplurality of frame rate instruction means to set a frame rate instructedby the frame rate instruction means that has the highest priority as aframe rate of a variable frame-rate picked-up image are provided so thatimage pick-up setting information may be generated which is used togenerate an image signal that is frame-synchronized with an image signalhaving the set frame rate of the variable frame-rate picked-up image,thereby properly setting a frame rate of a variable frame-rate picked-upimage and generating image pick-up setting information in accordancewith priority sequence even if the plurality of frame rate instructionsis issued.

Furthermore, the image signal generation means for generating an imagesignal of a variable frame-rate picked-up image and thedrive-and-control means for receiving image pick-up setting informationto generate an image signal that is frame-synchronized with an imagesignal of a reference variable frame-rate picked-up image, forcontrolling driving of the image signal generation means based on thisimage pick-up setting information so that the image signal generated bythe image signal generation means may be frame-synchronized with theimage signal of the reference variable frame-rate picked-up image areprovided. It is thus possible to generate an image signal that isframe-synchronized with an image signal of the reference variableframe-rate picked-up image.

Further, if frame rate information indicating a frame rate of areference variable frame-rate picked-up image is contained in imagepick-up setting information, starting from such a frame of a variableframe-rate picked-up image as to be given first after this image pick-upsetting information is input, a frame rate indicated by the frame rateinformation contained in this input image pick-up setting information isset as a frame rate of the variable frame-rate picked-up image, togenerate an image signal. It is thus possible to vary a frame rate of avariable frame-rate picked-up image in synchronization with the imagepick-up device that has supplied the image pick-up setting information.

Further, if the image pick-up setting information contains informationof a scan line position and a pixel position, a generated image signalis synchronized with these scan line position and pixel position.Therefore, it is possible to synchronize the image signal generated bythe image pick-up device that has supplied the image pick-up settinginformation, with the scan line position and the pixel position.Furthermore, if the holding means for holding frame rate alterationpatterns is provided and the image pick-up setting information containsinformation which is used to read the frame rate alteration patterns, aframe rate alteration pattern indicated by this information is read anda frame rate is instructed in accordance with the read frame ratealteration pattern, so that starting from such a frame of a variableframe-rate picked-up image as to be given first after the image pick-upsetting information is input, the instructed frame rate is set as aframe rate of a variable frame-rate picked-up image, to generate animage signal. Therefore, it is possible to alter the frame rate insynchronization with the image signal generated by the image pick-updevice that has supplied the image pick-up setting information. Further,the frame rate instruction means for instructing a frame rate of avariable frame-rate picked-up image and the operation control means forsetting priority sequence to the frame rate instructed by the frame rateinstruction means and a frame rate based on the image pick-up settinginformation so that the frame rate having higher priority may be set asa frame rate of a variable frame-rate picked-up image are provided, togenerate an image signal by using the frame rate of the variableframe-rate picked-up image as the set frame rate. Therefore, it ispossible to properly set a frame rate of a variable frame-rate picked-upimage based on the priority sequence even if a plurality of frame rateinstructions is issued.

Further, the synchronization signal generation device comprises thesetting information generation means for generating image pick-upsetting information which is used to frame-synchronize an image signalgenerated by the image signal generation means of the image pick-updevice with a reference frame, the synchronization signal generationmeans for generating a synchronization signal that corresponds to thisreference frame, the synchronization signal output means for outputtingthe generated synchronization signal with the generated image pick-upsetting information being inserted into it, and the control means forsetting the reference frame, so that it is possible to frame-synchronizethe image signals generated by the image pick-up devices connected tothe synchronization signal generating device.

INDUSTRIAL APPLICABILITY

As described above, the present invention enables to be generated theimage signals of a variable frame rate picked-up image which areframe-synchronized with each other by using a plurality of image pick-updevices, so that images of a subject are picked up in differentdirections by varying a frame rate, and could well be applied to a caseof obtaining special video effects such as fast reproduction and slowreproduction.

1. An image pick-up device comprising: image signal generation means for generating an image signal of a variable frame-rate picked-up image; drive-and-control means for driving and controlling the image signal generation means; setting information generation means for generating image pick-up setting information to generate an image signal which is frame-synchronized with the image signal generated by the image signal generation means, wherein the setting information generation means makes information of a scan line position and a pixel position of an image signal included in the image pick-up setting, said information being generated by the image signal generation means information; and output means for outputting the image signal generated by the image signal generation means and the image pick-up setting information.
 2. An image pick-up device comprising: image signal generation means for generating an image signal of a variable frame-rate picked-up image; drive-and-control means for driving and controlling the image signal generation means; setting information generation means for generating image pick-up setting information to generate an image signal which is frame-synchronized with the image signal generated by the image signal generation means; output means for outputting the image signal generated by the image signal generation means and the image pick-up setting information; and holding means for holding a frame rate alteration pattern, wherein when reading the frame rate alteration pattern held in the holding means and instructing a frame rate in accordance with this read frame rate alteration pattern to vary a frame rate of the variable frame-rate picked-up image, the setting information generation means makes information indicating the read frame rate alteration pattern included in the image pick-up setting information; and wherein the drive-and-control means drives and controls the image signal generation means, starting from a frame of the variable frame-rate pricked-up image that is given first after the image pick-up setting information is output, by setting the instructed frame rate as a frame rate of the variable frame-rate picked-up image.
 3. An image pick-up device comprising: image signal generation means for generating an image signal of a variable frame-rate picked-up image; drive-and-control means for driving and controlling the image signal generation means; setting information generation means for generating image pick-up setting information to generate an image signal which is frame-synchronized with the image signal generated by the image signal generation means; output means for outputting the image signal generated by the image signal generation means and the image pick-up setting information; a plurality of frame rate instruction means each for instructing a frame rate of the variable frame-rate picked-up image; and operation control means for setting priority sequence to the plurality of frame rate instruction means, to set a frame rate instructed by the frame rate instruction means that has the highest priority as a frame rate of the variable frame-rate picked-up image, wherein the setting information generation means generates image pick-up setting information which is used to generate an image signal that is frame-synchronized with an image signal having the set frame rate of the variable frame-rate picked-up image.
 4. An image pick-up device comprising: image signal generation means for generating an image signal of a variable frame-rate picked-up image; and drive-and-control means for receiving image pick-up setting information to generate an image signal that is frame-synchronized with the image signal of a reference variable frame-rate picked-up image, and controlling a driving operation of the image signal generation means based on this image pick-up setting information, thereby frame-synchronizing the image signal generated by the image signal generation means with the image signal of the reference variable frame-rate picked-up image, wherein, if the image pick-up setting information contains frame rate information indicating a frame rate of the reference variable frame-rate picked-up image, the drive-and- control means drives the image signal generation means, starting from a frame of the variable frame-rate picked-up image that is given first after this image pick-up setting information is input, by setting a frame rate indicated by the frame rate information contained in the input image pick-up setting information as a frame rate of the variable frame-rate picked-up image.
 5. An image pick-up device comprising: image signal generation means for generating an image signal of a variable frame-rate picked-up image; and drive-and-control means for receiving image pick-up setting information to generate an image signal that is frame-synchronized with the image signal of a reference variable frame-rate picked-up image, and controlling a driving operation of the image signal generation means based on this image pick-up setting information, thereby frame-synchronizing the image signal generated by the image signal generation means with the image signal of the reference variable frame-rate picked-up image, wherein, if the image pick-up setting information contains information of a scan line position and a pixel position, the drive-and-control means synchronizes an image signal generated by the image signal generation means with the scan line position and the pixel position.
 6. An image pick-up device comprising: image signal generation means for generating an image signal of a variable frame-rate picked-up image; drive-and-control means for receiving image pick-up setting information to generate an image signal that is frame-synchronized with the image signal of a reference variable frame-rate picked-up image, and controlling a driving operation of the image signal generation means based on this image pick-up setting information, thereby frame-synchronizing the image signal generated by the image signal generation means with the image signal of the reference variable frame-rate picked-up image; and holding means for holding a frame rate alteration pattern, wherein, if the image pick-up setting information includes information which is used to read the frame rate alteration pattern, the holding means reads the frame rate alteration pattern indicated by this information and instructs a frame rate in accordance with this read frame rate alteration pattern; and wherein the drive-and-control means drives the image signal generation means, starting from a frame of the variable frame-rate picked-up image that is given first after the image pick-up setting information is input, by setting the frame rate instructed by the holding means as a frame rate of the variable frame-rate picked-up image.
 7. An image pick-up device comprising: image signal generation means for generating an image signal of a variable frame-rate picked-up image; drive-and-control means for receiving image pick-up setting information to generate an image signal that is frame-synchronized with the image signal of a reference variable frame-rate picked-up image, and controlling a driving operation of the image signal generation means based on this image pick-up setting information, thereby frame-synchronizing the image signal generated by the image signal generation means with the image signal of the reference variable frame-rate picked-up image; frame rate instruction means for instructing a frame rate of the variable frame-rate picked-up image; and operation control means for setting priority sequence to the frame rate instructed by the frame rate instruction means and the frame rate based on the image pick-up setting information, to set the frame rate that has higher priority as the frame rate of the variable frame-rate picked-up image, wherein the drive-and-control means drives the image signal generation means by using the frame rate of the variable frame-rate picked-up image as the frame rate that is set by the operation control means.
 8. The image pick-up device according to claim 7, wherein, if input of the image pick-up setting information is stopped when higher priority is set to a frame rate based on the image pick-up setting information than a frame rate instructed by the frame rate instruction means, the operation control means sets a frame rate set before the input of the image pick-up setting information as the frame rate of the variable frame-rate picked-up image.
 9. The image pick-up device according to claim 7, wherein, if input of the image pick-up setting information is stopped when higher priority is set to a frame rate based on the image pick-up setting information than a frame rate instructed by the frame rate instruction means, the operation control means sets a frame rate at the time when the input of the image pick-up setting information is stopped, as the frame rate of the variable frame-rate picked-up image. 